An embarrassing faux pas of Google’s algorithm is the ridiculous claims that a page is at the top based on popularity, not accuracy.

A quick search for ‘ smallest animal in the world ‘ will turn up a diminutive mammal that, although small for a furry, alert creature, is still larger than the vast majority of animals on the planet. Earth.

Luckily, we’re here to take care of things.

The majority of animals are arthropods. This is true both in terms of species numbers and biomass.

In fact, the phylum Arthropoda, which contains all invertebrates with “jointed legs” such as insects and arachnids, contains more species than all other phyla combined. ^{twelfth _}

Insects make up the majority of this phylum, and most of them are smaller than the smallest mammals.

So in the final ranking, the Etruscan shrew, shamelessly considered the smallest animal, is actually much closer in size to the African elephant than the smallest animals on the planet. pure.

This kind of biological pedagogy is what we live for, so we’ve put together a series of three lists:

1. The smallest animals on land
2. The smallest animals in the air
3. The smallest animals in the water

Since the smallest animals are actually all relatively similar and we wanted to give you a list of 30 species of microscopic nematodes with names like Caenorhabditis elegans , we divided them into categories and chose instead smallest.

Smallest land animals (by type)

1. Smallest mammal – Etruscan shrew (40 mm)

The smallest mammal is ready to pounce and dive down the tether between the furry bat and this little guy, the Etruscan shrew.

As the bat wins the trophy for smallest aerial mammal, the shrew wins the trophy.

The Etruscan shrew weighs only 1.8 g and is the smallest mammal by mass. At 40mm long, you’d be lucky to find a shorter mammal on the ground too.

They are widely distributed throughout Southern Europe, the Middle East, North Africa and Asia, and spend all their time eating, grooming or sleeping. ³

2. The smallest insect – Dicopomorpha echmepterygis (0.14 mm)

The smallest insect is the wasp, which is in the same family as the smallest flying animal.

This one is a male of another species and has no wings, but it was found to be significantly smaller than its flying cousins.

This wasp is so small that it is shorter than some species of amoeba and bacteria. They do nothing more than take over their host’s eggs to parasitize and mate with much larger females of the species. ⁴

3. The smallest elephant – Palaeoloxodon falconeri (1 m high)

We’re making an exception for an extinct animal, which is a perfect illustration of insular dwarfism.

Descendant of P. giant, four meters high. antiquus , this tiny elephant got stuck on an island in Italy and started to shrink.

At around 1 meter tall, these are the smallest elephants that we know of to have existed anywhere and would make good pets.

4. Smallest primate – Madame Berthe the mouse lemur (92 mm)

This 30g lemur is another example of a small island animal. It averages less than 10cm long and is one of many lemur species in Madagascar.

Berthae is just one of a large population of mouse lemurs on the island, and like many other species, it is critically endangered.

The increase in slash-and-burn agriculture has devastated the species’ forest habitat and numbers are still decreasing. ⁵

5. Smallest scorpion – Microtityus minimus (11.4 mm)

This species was recently discovered in 2014, so not much is known about it, other than that it is very small.

Just over a centimeter long, this little warbler must be very good at finding smaller animals to eat.

They are found in the southern foothills of the Central Cordillera Mountains in the Dominican Republic, but their distribution has not been established.

6. Smallest lizard – Jaragua Dwarf Gecko (16 mm)

The Jaragua dwarf lizard, discovered on an island off the coast of the Dominican Republic, is the smallest known reptile.

Adults are only 1.6 cm long and there may be smaller ones to explore. What’s surprising is that for a tiny animal on an inhabited island, these lizards seem to be doing fine and have everything they need for a stable population, despite deforestation in area is increasing.

This is a classic example of island shrinking, in which isolated animal communities evolve to become smaller and smaller due to fewer resources.

7. Smallest frog – Paedophryne amauensis (7.7 mm)

The world’s smallest frog is from Papua New Guinea and is considered the smallest vertebrate.

It is significantly under 1cm in length with 7.7mm from nose to tail, and although it is slightly shorter than the smallest fish, it is also heavier, making the difference between them negligible.

They live well above sea level, at altitudes of 150-800 meters in moist forest habitats.

8. Smallest spider – Patu digua (0.37 mm)

This male spider was found with a slightly larger female spider of another species.

Since females are usually significantly larger, it’s been proposed that the male of the Anapistula caecula species may be even smaller than this little guy, but until then, he still holds the record.

Males of this species are about 0.37mm long and are found in Colombia. They are dwarf orb-weaving spiders, similar to common garden spiders, but very, very small!

9. Smallest Collembola – Springtail (0.2 mm)

Springtails can be found all over the world, under almost any rock or log, yet very few people have ever seen one. That’s because they’re so small!

Most of the largest springtails are only a millimeter or two long, and the smallest are almost impossible to detect.

They are closely related to insects, but form their own order, Collembola, and the shortest species we can find is 0.2mm long.

They are also very important decomposers, occupying the top layers of soil and recycling nutrients from leaf litter.

10. The smallest worm – Protorhabditis hortulana (0.2 mm)

80% of all animals are nematodes. Their abundance is greater than that of any other life form and they inhabit every habitat and occupy countless niches.

So it’s likely that the smallest animals on earth are nematodes, and this species is a good place to start.

Discovered in a compost pile near the Iberian Peninsula, it represents one of countless nematode species of its size and is one of the smallest animals on earth at less than 0.2mm in length.

11. The smallest tick – Demodex brevis (0.1 – 0.2 mm)

Ticks can be among the most useful and most destructive animals. Some provide amazing ecosystem services, while others spread terrible diseases.

One type that causes major damage to crops is the tomato red spider mite, an example of which is very small at 0.2mm in size.

To put it into perspective, these mites are about the same size as Demodex brevis , these mites are found at the base of your eyelids, feeding on your sebum juices which you may not have known about until now…

Eyelash mites can be even smaller than tomato mites and are around 0.1mm in size.

The smallest animals in the air (by species)

Insects are the only flying arthropods, which means there will be no spiders, mites, ticks or scorpions on this list, and that’s a shame. However, check out this list of smallest land animals for some of these!

However, there are still quite a few interesting birds and even bats to look at as well as many different types of flying insects to get your hands on. Let’s see!

1. Smallest bird – Bee hummingbird (6 cm)

Hummingbirds are famous for being light for their size, but this bee hummingbird makes it look incredibly light.

Weighing just over 2g and measuring about 6cm long, this is the smallest known bird and lives only in Cuba.

As a flower provider, it pollinates plants as it moves from flower to flower, maintaining a daily routine of over a thousand flowers to meet its energy needs. ⁶

2. Smallest raptor – Black-thighed falcon (15 cm)

This tiny raptor has pushed the boundaries of miniature birds of prey.

It is only slightly larger than a sparrow, about 15cm tall, and since most other birds are larger than it, it also hunts insects and lizards.

However, this is a powerful little falcon that can handle prey its own size and, at just 35g, it is an impressive little bird hunter.

3. Smallest bat – Kitti pig-nosed bat (2.5 cm)

This is a top contender for the title of smallest mammal, which would make Google’s top result for “smallest animal” doubly inaccurate!

These tiny pig-nosed bats occupy caves and come out to forage for short trips at dusk before larger animals realize they are around.

These bats are only known to exist in a single province of Burma and a small region of Thailand, and although their true distribution is unknown, they are currently considered Near Threatened.

Also known as the art bat, it weighs about 2 grams and is slightly heavier, but smaller in length than the Etruscan shrew at about 2.5 cm in length. ⁷

4. Smallest butterfly – Sinai baton blue (14 – 18 mm)

When we removed the bulky bones and spines of the smallest vertebrates, we began to see rapid reductions in size.

The smallest known butterfly has a Sinai baton blue color and a small wingspan of only 14-18 mm making it one of the cutest butterflies.

This butterfly has been studied in conjunction with research on global warming and habitat fragmentation and is currently listed as critically endangered by the IUCN due to both factors.

5. Smallest moth – Stigmella maya (2.8 mm)

But the blue baton Siniai is not the smallest Lepidopteran, that title belongs to a Mexican species known only as Stigmella maya .

This exceptionally small moth can have a wingspan of just 2.8 mm and is just one of hundreds of small moth species.

Its larvae are small enough to burrow between the layers of the host plant’s leaves.

6. The smallest bee – Perdita minima (2 mm)

Since almost every small thing seems to be named after a bee, let’s see how small a bee can be!

Bees are a lot more diverse than people realize. There are an estimated 20,000 species of bees and thousands of species can be found in most non-freezing countries.

The smallest bee recorded to date was found in Texas and is much smaller than the eyes of some of the largest bee species.

Perdita minima is a pollinator and grows to about 2 mm in length. Although it is the smallest known bee species, it is hardly the smallest species out there as thousands of species remain undiscovered and much of the African continent remains understudied.

7. Smallest dragonfly – Scarlet dwarf (20 mm)

This small predator is known as the Scarlet Dwarf. This isn’t a very scary name, but don’t be fooled; Like all dragonflies, the smallest recorded species is an aerobatic aerobatic, able to fly backward, change direction in the blink of an eye, and reach the fastest speeds of any flying insect. .

This one reaches the upper limit of about 20 mm across and is often found patrolling abandoned rice fields in Asia.

While the species is doing well globally, local populations are threatened by habitat fragmentation.

8. Smallest fly – Euryplatea nanaknihali (0.4 mm)

Now we are talking about one of the smallest insects and the smallest true fly at 0.4mm in length!

This species is a parasite of ants and is said to lay eggs in their heads. Because it is so small, there is still a lot to understand about this animal, but this family has been recognized by science.

Phoridae flies are said to be one of the most diverse insect families, as well as having the most diverse size range of any insect family.

As parasites, they have a significant influence on the population dynamics of their hosts, and this relatively new discovery opens up more questions about the smallest insects possible. ⁸

9. Smallest beetle – Scydosella musawasensis (0.3 mm)

A Colombian beetle has set a record for being the smallest beetle among the most diverse animals on the planet. About a quarter of all animal species are beetles and they make up almost half of all insect species, so there’s a lot of competition!

This tiny beetle is 0.3mm long and it is not only the smallest beetle but also the smallest free-living insect on record.

10. Smallest flying animal – Megaphragma caribea (0.2 mm)

The smallest flying insect appears to be M. caribea of Guadaloupe, measuring about 0.2 mm.

This is a type of Fairyfly but not a real fly at all. The fairy butterfly is actually a type of parasitic wasp and is the smallest recorded insect.

In many species, the males are flightless, making them unsuitable for this list despite being the smallest recorded insects, but the winged females of this species are still small enough to compete.

These wasps are so small that there isn’t even enough space in the nerve cell for the cell nucleus. They are the subject of research into how miniaturization works and the sacrifices an animal needs to make to become small. ⁹

The smallest aquatic animals (by type)

1. The smallest fish – Paedocypris progenica (7.9 mm)

This may be the smallest known vertebrate. Paedocypris fish is a type of freshwater carp that lives in peat bogs and wetlands in Indonesia.

They are listed as Near Threatened due to habitat degradation, as peat bogs are being routinely destroyed to make way for crops such as oil palm and shrimp farms.

Paedocypris progenica is so named because of its immature appearance, retaining its larval morphological characteristics until sexual maturity. ^ten

2. Smallest swimming mammal – American water shrew (120mm)

This tiny water shrew is only semi-aquatic, but it deserves mention for its diminutive size and status as the smallest diving mammal.

It is found in the US and Canada and weighs only a maximum of 18g. Large examples can grow up to 17cm, but they are usually small at just 12cm long.

They have special olfactory organs on their faces that allow them to smell underwater and will attack anything that wiggles.

3. Smallest shark – Dwarf lantern shark (200 mm)

Since we’ve handled the biggest sharks, it’s only fair that we praise the smallest sharks. Lantern sharks are a small group, and dwarf lantern sharks are the smallest of the bunch.

This is a relatively unknown species, even for a shark, but one thing that stands out is how petite it is.

It is a 20 cm long shark, found just below the photic zone and is currently the smallest shark we know of. ¹¹

4. Smallest crab – Bean crab (15 mm)

Crab pea makes itself right at home inside an edible clam, which is probably the only reason we know about it.

At best, this animal is about 1.5cm across and only about 7mm from front to back. It is one of a group of pea crabs that live inside this host; unfortunately has the name fat clam. ^twelfth

5. Smallest jellyfish – Malo kingi (5 mm)

The Irukandji jellyfish belongs to the genus Malo, this species is known as the king killer, named after one of its victims, Robert King.

These are small but deadly jellyfish found off the coast of Australia. At half a centimeter in size, they are almost undetectable, which makes studying them difficult.

Their venom is particularly strong and produces such a unique physiological response that people call them Irukandji. ¹³

6. Smallest aquatic insect – Beetle (1 mm)

Although there are many invertebrates in the ocean, there are really no insects that live in marine environments – crustaceans occupy most of those niches.

And in freshwater, there are very few species that live entirely in water throughout their entire life cycle.

Many insect species have life stages that involve living in water, but only a small fraction of these remain in the water as they mature.

Riffle bugs can survive for at least 9 years without leaving the water, which qualifies them for this list.

Of the 5,000 species of beetles, it’s impossible to be sure which is the smallest, but Oulimnius tuberculatus is a good candidate.

At 1mm long, it is one of the smallest aquatic insects.

7. Smallest bivalve – Condylonucula maya (0.5 mm)

From giant clams to microscopic mollusks, we have the smallest bivalve currently recognized.

This tiny clam is only half a millimeter long, smaller than many grains of sand it can find!

8. The smallest copepod – Sphaerellopsis monothrix (0.1 mm)

A lot is going on in the world of ocean zooplankton, and while the ‘zoo’ part of the word refers to animals and distinguishes them from photosynthetic algae (plants), it does include Other organisms are no longer considered animals, such as single-celled organisms.

With that in mind, the smallest zooplankton may be copepods like S. monothrix , which can be as small as 0.1mm .

These parasitic plankton make up a large part of the ocean food web and live in their own little world, drifting through the ocean just like we are a planet drifting through the galaxy without control where we go.

9. Smallest worm – Ocean nematode (0.08 mm)

Nematodes are everywhere. C. elegans in the introduction is an example of a nematode, which is both free-living and parasitic, and makes up some of the largest and smallest worms in the world.

The ocean is home to both ends of this spectrum, including an 8-meter-long parasitic whale, and although it is also home to the smallest, there are a number of candidates for that title.

What we do know is that both Desmoscolex sp. and Greeffiella species are about 0.08mm in size, making them one of the smallest aquatic animals and substantiating the claim that the list is truly the smallest animals to be infested with worms .

10. Smallest swimming arthropod – Tantulacus dieteri (0.08 mm)

This may be the smallest arthropod in the world. With a recorded length of 0.08mm, this parasitic crustacean is definitely the smallest animal we can find on this list.

Like its crustacean neighbor, this animal will float uncontrollably, attached to its host in the plankton soup that forms the nutritional foundation for all larger animals.

Final thoughts

So that concludes our list of the smallest animals in the world , on land, in the air, and in the sea, by type.

Let’s find out why smaller animals are so much more successful than their larger neighbors.

Benefits of being small

Most animals are small. As humans, we have about 100 trillion cells and that’s just in our tissues. In our gut there can be anywhere from 15 trillion to 724 trillion bacteria, pushing the volume up to 800 trillion cells or more.

In the animal kingdom, although there are significant variations in size, the cells that make up each animal are of a similar scale (there are some fairly obvious exceptions to this rule: eggs The ostrich is an example of an animal cell about 15cm across).

Returning to our friend C. elegans, which has about 2,000 cells, this means we are hundreds of billions of times the size of the smallest multicellular animals.

In contrast, an elephant might weigh no more than a hundred times our mass, and the difference between a 7-tonne mammoth and a 1g baby shrew is still only seven million.

So, being small is common and there are many reasons for this.

Being small means you can reproduce faster. Cell division doesn’t take as long with 2,000 cells as it does with hundreds of trillions, and this can be an advantage.

Next is real estate supply. Going tiny really opens up your options for where you can live.

You don’t need to eat much because your biology is relatively simple and in many cases you can reproduce in air or water.

Being big is good for some things, but when extinction events inevitably occur, large animals will be the first to perish.

The mammals that survived the extinction of the dinosaurs were tiny and only grew to giant sizes after niches previously held by their reptilian overlords became new. .

Isolation on islands often results in smaller animals due to the increased efficiency of having smaller stomachs.

So the animals on this list know what they’re doing.

The problem with being small

Small animals are much harder to find than larger animals, causing this list to change significantly the closer we look.

Almost every tiny animal on this list was discovered in the last decade or three, which shows how long it can take to find them!

Factual Sources & References

1. Iman Ghosh (2021), “All the Earth’s Biomass, in One Graphic,” Visual Capitalist.
2. “Phylum Arthropoda“, Exploring our Liquid Earth.
3. “Top 10: Smallest mammals on Earth“, Science Focus.
4. Edward L. Mockford (1997), “A new species of Dicopomorpha (Hymenoptera: Mymaridae) with tiny, winged males,” Annals of the American Entomological Society.
5. Markolf, M., Schäffler, L. & Kappeler, P (2022), “Microcebus berthae”, IUCN Red List of Threatened Species 2022.
6. Eric R. Miller, Murray E. Fowler (2015), “Fowler Zoo and Wildlife Medicine, Volume 8“, Google Books.
7. “Bumblebee bat (Craseonycteris thonglongyai)“, Edge of Existence.
8. Ed Yong (2012), “The world’s smallest fly may have decapitated very small ants”, National Geographic.
9. Alexey A. Polilov (2017), “First record of Megaphragma (Hymenoptera, Trichogrammatidae) in Columbia, and the third animal known to have nucleated neurons,” Journal of Hymenoptera Research 60.
10. Maurice Kottelat (2005), “Paedocypris, a new genus of Southeast Asian carp with remarkable sexual dimorphism, is the world’s smallest vertebrate”, Proceedings of the Royal Society.
11. “Dwarf Lantern Shark,” Smithsonian.
12. Zmarzly, Deborah L (1992), “A taxonomic review of pea crabs of the genus Pinnixa (Decapoda: Brachyura: Pinnotheridae) occurring on the California shelf, with descriptions of two species”, Crustacean Biology.
13. “Weird Science: Deadly Box Jellyfish”, Exploring Our Liquid Earth.